1. Technical Field
The present disclosure generally relates to drainage devices, and particularly, to a drainage device for draining liquid out of a closed chamber.
2. Description of the Related Art
In the discharging of sewage, sewage is generally sucked into a container to be purified by a sewage suction cleaner, and is then discharged to the outside. The sewage suction cleaner includes a closed chamber and an air pump. The closed chamber achieves a certain degree of vacuum by using the air pump. Under the air pressure, the sewage is pushed into the closed chamber. However, when discharging the sewage, outside air will flow into the closed chamber via a sewage discharging outlet, and thus the degree of vacuum obtained of the closed chamber is decreased. As a result, the air pressure difference between the inside and the outside of the closed chamber is decreased, and sewage is not forced into the closed chamber as expected.
Therefore, there is room for improvement within the art.